The present invention relates to a loading device for agricultural harvesters, in particular for a self-propelling field chopper.
Loading devices of harvesters are used for transferring of products harvested with an agricultural machine, such as for example green product, fodder grain, leguminous and other stalk fruits, to a transporting vehicle which supplies the harvested product, in some cases also processed, to its further predetermined use. Such loading devices are known in various embodiments and have a generally common principal construction. The loading device usually has a lower discharge chute in which in many applications a post-accelerator for the product discharge is arranged, and a freely standing upper discharge chute which is formed of one piece and closable by an adjustable ejection flap. The upper discharge chute is flanged on the lower discharge chute of the harvester rotatably through a rotary rim about a vertical axis. In the region of the connecting point it is articulatingly connected so as to be vertically adjustable about its rotary point. In this way the product stream can be deviated and dispersed so that the available transportation volume of the transportation vehicle is used as fully as possible and a loss-free product transfer is guaranteed. The ejection flap mounted on the end of the upper discharge chute serves the same purpose. Its working positions are adjustable by means of a hydraulic adjusting device.
The principal construction and operation of these loading devices have been proven efficient in practice during loading of transporting vehicles which are available through a not closed, upwardly open loading space.
For transportation of the harvested, chopped and in some cases conditioned products from the cultivating area, also transporting vehicles with a closed loading space are used, wherein the product stream is supplied through a loading opening in the transporting space. For the product transfer, the transporting vehicle must move laterally as close as possible to the harvester. The loading of the transporting vehicle through a side opening is not without problems in this case because of the relatively long upper discharge chute of the loading device. The loss-free product transfer from the harvester to the transporting vehicle requires a substantially high driver's skills and improved control by the operator of the harvester, to provide a substantially loss-free product transfer during deviations of the upper discharge chute due to ground uneveness.
It is further known during harvesting of green products, leguminous plants and stalk fruits that ground material, such as sand adhering to the harvested product is taken and supplied by the attachment into the harvester. When the harvested product is preprocessed and prepared in the chopping and conditioning device and discharged through the post-accelerator, the ground particles which are contained in the processed harvested product positively transfer a high kinetic energy. Therefore, the friction forces apply high loads to the upper discharge chute, namely in the impact region, which leads to a premature wear of the upper discharge chute. This wear process is advanced by the acid content of the plant juices released in the chopping and conditioning process.
In order to increase the service life of the upper discharge chute and minimize required maintenance work and service rates, the upper discharge chute is provided with exchangeable wear plates in the impact region and on the side walls. With increasing wear of these plates, which is determined only during inspection and maintenance works, cracks and wear-caused deformations occur in the plates, in which the discharged harvested product deposits very fast. This leads to clogging during the harvesting process in a relatively short time, so that undisturbed working process is no longer performed and these deficiencies can be eliminated only by expensive manual work.